In electronic parts such as liquid crystal display devices, integrated circuit devices and solid image forming devices and color filters for liquid crystal displays, functional resin films for electronic parts such as protective films for preventing degradation and damages of devices and displays, flattening films for flattening the surface of the devices and wiring and electric insulation films for maintaining the electric insulation are disposed. In liquid crystal display devices of the thin film transistor type and integrated circuit devices, interlayer insulation films for insulation between wirings arranged as layers are disposed as the functional resin films for electronic parts.
However, occasionally, an interlayer insulation film having sufficient flatness cannot be formed even when a thermosetting material heretofore known as the material for forming electronic parts is used, and a novel material sensitive to radiation which is used for forming insulation films and enables fine patterns to be formed has been desired. Moreover, as the density of the wiring and the devices increases recently, the desired material is required to have a small permittivity.
In response to the above requirement, compositions comprising an alicyclic olefin resin soluble in an alkali which is obtained by ring-opening polymerization of a norbornene-based monomer having an ester group, followed by hydrogenation of the obtained polymer and hydrolysis of the ester group portion to form bonded carboxylic group, an acid-generating agent and a crosslinking agent, are proposed (Japanese Patent Application Laid-Open Nos. Heisei 10(1998)-307388 and Heisei 11(1999)-52574).
However, it has been confirmed by the present inventors that the resin films formed by using the radiation sensitive resin compositions described in the above two patent publications have poor storage stability and property for development although permittivity, water absorption, flatness, solvent resistance and dimensional stability under heating are excellent. Since a radiation sensitive resin composition is used in an industrial process, in general, after the composition is prepared in a suitable vessel and, then, transferred to an apparatus for applying to a substrate or the like, the storage stability of the composition is very important.
As the result of intensive studies based on the above knowledge by the present inventors to obtain a radiation sensitive resin composition which is suitable for industrial process, it was found that an alicyclic olefin resin soluble in an alkali could be obtained without the hydrolysis step when an alicyclic olefin monomer having an acidic group such as carboxyl group was polymerized in the presence of a catalyst containing ruthenium (a ruthenium catalyst) and the obtained polymer was hydrogenated in place of obtaining, as specifically described in examples of the above publications, an alicyclic olefin resin by ring-opening polymerization of an alicyclic olefin monomer having an alkyloxycarbonyl group in the presence of a catalyst containing tungsten (a tungsten catalyst), followed by hydrogenation of the obtained polymer and hydrolysis of the hydrogenation product to obtain carboxylic acid, and that the resin obtained by the present inventors exhibited the storage stability suitable for the industrial process and provided a radiation sensitive resin composition exhibiting an improved property for development. The present invention has been completed based on the above knowledge.
Patent Reference 1                Japanese Patent Application Laid-Open No. Heisei 10(1998)-307388        
Patent Reference 2                Japanese Patent Application Laid-Open No. Heisei 11(1999)-52574        